Powder spreaders suitable for use with layered manufacturing processes are disclosed in which a strip of flexible material of a width which spans the powder bed is used to spread, level, and, optionally, compact deposited powder to form a layer of the powder bed. The strip surface moves relative to the deposited powder it is spreading as the working portion of the strip, i.e., the portion of the strip that is in contact with the powder, traverses across the powder bed so that it can provide lift to the powder in front of it and, optionally, compaction to the powder below it. The working portion of the strip can be configured to have its leading and trailing surface contours to be different from one another, and, optionally, to have these contours and its bottom edge contour be independently adjustable. Layered manufacturing systems comprising such powder spreaders are also disclosed.